from itsdangerous import TimedJSONWebSignatureSerializer as Serializerfrom django.conf import settingsfrom itsdangerous import BadDatadef generate_save_user_token(openid):    """对openid进行加密"""    # 1.创建序列化器对象    serializer = Serializer(settings.SECRET_KEY, 600)    data = {'openid': openid}    # 2.调用序列化器的dumps    access_token_bytes = serializer.dumps(data)    # 3.把加密后的openid返回    return access_token_bytes.decode()def check_save_user_token(openid):    """对加密的openid进行解密"""    # 1.创建序列化器对象    serializer = Serializer(settings.SECRET_KEY, 600)    try:        # 2.调用loads方法对数据进行解密        data = serializer.loads(openid)    except BadData:        return None    else:        return data.get('openid')